Safety shutoff valve mechanism



SWL 23 1947 T. F. VAN DENBERG E'r AL 2,427,935

SAFETY SHUT-OFF VALVE MECHANIS 2 Sheets-Sheet 1 4INV-EN TORJ VAN Ds.enna f J'o BY 'mijn f 197' TORNEY,

HN LLLY Wam FT' Filed Nov; 27, 1944 1 l I. r

T. F. VAN DENBERG Er AL 2,427,935

SAFETY SHUT-OFF VALVE MECHANISM Filed Nv. 27,v 1944 y sept. 23, 1947,

I 2 Sheets-Sheet "2 IN VENTORJ.

Momes Fz-'VANDLNBLRG JoHN amv iatented Sept. 23, 1947 UNITED STATESPATENT OFFICE SAFETY SHUTOFF VALVE MECHANISM g, Cleveland Heights, and

Ohio, assignors to The Titan Valve and Manufacturing Company,Cleveland', Ohio, a corporation of Ohio Application November 27, 1944,Serial No. 565,210

Thomas F. Van Denber John Selby, Euclid,

4 Claims.

This invention relates to safe control mechanism, such as is used forsafeguarding the supply of fuel to a burner against the possibility ofaccident or injury as the result of extinguishment oi a pilot light forthe burner.

The invention has more particular relation to that class of safetydevices in which a single control device, such as an electric switch,valve member,7 or lthe like is movable back and forth between idle orsafe position and active or operating position, being releasably held inthe operating position by maintaining meanssensitive to variations in acondition, such as temperature, the maintaining means and control devicebeing separately actuated to maintaining position and operatingposition, respectively, by the independent advance and retraction of areset or cooking device.

One object of the invention is to provide improved control mechanism ofthe character described which reduces the number of necessary parts,simplifies the construction' and secures more reliable and certainoperation.

Another object is to provide improved mechanism of this kind in whichall parts are arranged symmetrically about a common axis.

A further object is to provide control mecha- .nism of this kind inwhich the casing or enclosing housing is in one piece and all workingparts may be assembled on the bench in one unit for insertion into andattachment to the casing.

Still another object is to provide control mechanism of this kindembodying maintaining means in the form of cooperating magnet andarmature members, one of which is attached to and is carried by acentral stem upon which the cocking device is sleeved and slidable.

Finally, another object is to provide improved control mechanism of thiskind in which alloperating parts are assembled and supported upon asingle stem or rod which forms one of the operating parts for the pilotvalve and also serves as a guide for the movable main or shutoff valve.

Further objects of the invention in part are obvious and in part willappear more in detail hereinafter.

In the drawings, which represent one suitable embodiment of theinvention,

Fig. l is a longitudinal sectional elevation, showing the parts innormal safe or idle position;

Fig. 2 is a similar view, showing the cooking device advanced, certainparts being omitted;

Fig. 3 is a similar view illustrating all parts in the active oroperation position;

Fig. 4 is a cross section on the line 4 4, Fig, 1; and.

Fig. 5 is a cross section on the line 5-5, Fig. 3.

While the invention may be applied for use in the operation of any kindof control devices, such as an electric switch, a valve, or the like,for convenience, and in no sense of limitation, it has been illustratedin a form including `a valve for controlling the flow of fuel to aburner. The drawings illustrate valve mechanism including a lhollow bodyor casing IIB, which is a single integral member, in which is a safetyshutoff valve I I controlling the ow of fuel, such as gas, through anopening in a cross wall I2 dividing the cavity within the hollow bodyinto supply and discharge chambers I3, III, the former communicatingwith a supply conduit I5 andthe latter with a conduit I6 leading to themain burner I1. `The l I8, being biased to move toward closed positionbyin a compression spring I9. Tube I8 is sleeved upon.'`

an operating rod or stem 2U biased for outward'` iv movement, or to theleft in Fig. 1 by a compres- The outer endvof rod 20 is en--l-zy closedwithin a cap 22 attached to the tube I8, and the outer end of which capforms a push button for depression by the operators iinger, to

sion spring 2 I.

enable the cooking or resetting operation to bev performed. Tube I8 isbiased for outward movement, or to the left in Fig. 1, by thecompression spring 23, which, at its inner end, abuts a washer 24 whichconfines in place a sealing device, such as the O ring 25 seated againstan inwardly extending iiange 28 of a thimble 2l screwed into the casingand to which all of the operating parts are connected.

The valve III is movable back and forth, by sliding movement on or withtube I8, between the normal safe or inactive position shown in Fig. 1and the operating position shown in Fig* 3. When moved thereto, it maybe maintained or held in the operating position by any suitable holdingmeans, preferably operated by the cocking device. These holding meansmay be of any suitable form, such as a latch, or an electromagnet andarmature energized by any suitable source of current, such as athermocouple, but in the form shown the holding devices include the twomembers of a permanent magnet couple of the same general form andoperating in the same general manner as those described and shown in aprior application forv Safety valve mechanism, Serial No. 558,514, iiledOctober 13, 1944, by Van Denberg and Selby, to which reference may behad if necessary or desirable, Either or both of the members of themagnet couple may be movable. In the arrangement shown the amaturemember 28 is of washer form and firmly anchored or fixed in the body orcasing. Its coop-4 erating mating member is the permanent magnet 28mounted upon and movable with the stem 20, which also carries a sealingring 3|! adapted to seat upon an annular flange on the inner end of thevalve member II for preventing gas leakage through the working joints.

Upon the inner end of the stern is threaded an enlarged extension 3|,serving as a pilot valve, for which purpose it is provided with anannular groove 32 cooperating with a channel 33 communicating at one endwith a pilot gas supply pipe 34 and at its opposite end with the tube ofthe pilot burner 35, located adjacent to the main burner II. The stemextension 3| also serves as one of a. pair of stop abutments controllingthe production of the holding or maintaining eiIect. This itaccomplishes by cooperation with an adjustable stop device sensitive tovariations in an operation condition, such as variations in thetemperature resulting from presence or absence of pilot flame. In thearrangement shown I provide a thermostatic device of tube and rod form,including a tube 38 and a rod 31, one of which, such as tube 36, may bemade of material expansible by heat, such as brass or copper, and theother of which may be made of relatively nonexpansible material, such asinvar, or vice versa. To avoid the effects of variations in ambienttemperature a push rod 38 is interposed between the inner end of the rod31 and the stem extension 3|, said push rod being made of materialhaving the same coeillcient of expansion under heat as that of the tubeIl.

As will appear hereinafter, during the cooking operation, upon advanceof tube IB and stem 20 to the right in Fig. l, the holding ormaintaining devices are adjusted near to each other, but short of actualcontact, ready for the production of maintaining effect. subject to theappropriate or necessary variation in temperature. This adjustment isproduced without effect upon the shutoff valve II which remains in itssafe or closed position. Its movement to operating position is initiatedor produced by the return or retracting movement of the cooking partsafter the holding effect is secured. For that purpose means is providedfor making the cooking parts effective upon the valve for opening itduring the latter portion oi' the cooking operation. To this end thestem 20 is provided with an annular external groove 39 having inclinedend walls, and the inner cylindrical wall of valve II is provided withan annular recess 40, which annular recesses cooperate with one or moreballs 4| (two, three or more of which may be used) each of which balls Ais confined in an opening 42 in the tube I8, as the result of Iwhich theballs move back and forth with the tube during its endwise movement andare also capable of inward or outward movement radially of the centralaxis, without escape from the tube opening.

The valve mechanism described operates as follows:

Fig. 1 illustrates all parts in the normal safe or inactive position.The pilot valve is closed, so that no gas flows to the pilotburner. Thesafety shutoff valve |I is also closed so that no gas flows to the mainfburner. The pilot valve is held closed by spring 2 I, which is somewhatweaker than spring I! which holds the shutoff valve closed. Sealing ring30 prevents gas escape 4 through the operating joints. The balls 4I restin the annular groove 39 in stem 20 and lie opposite a cylindricalportion of the opening in valve I I. v

To set the parts into operation pressure is applied to the outer end ofcap 22. The first effect is to take up any lost motion between the innerend of tube I8 and the shoulder on rod 2|) at the sealing device 30.Then the rod 20 and tube I8 move together tothe right to the positionshown in Fig. 2, where the end of stem extension 3| has engaged the endof the push rod 38, with all lost motion taken up. Annular groove 32 isnow opposite the pilot channel 33 so that gas flows to the pilot burner.However, as in the prior application before referred to, the two membersof the permanent magnet couple are not yet in actual contact with eachother, being separated by a space of the order of .020 of an inch.Therefore, if the cooking device is released the parts return to theiroriginal positions, shutting oi the pilot gas supply. However, ifthepilot burner is ignited the flame jets from its burner ports playupon the thermostatic device and expand the tube thereof, in the formshown, so that the /thermostatic rod 31 and push rod 38 move to theright until the permanent magnet reaches actual contact with thearmature, with a holding or maintaining effect. The ,inclined wall atthe left-hand end of the annular groove 39 in stem 20 is at the right ofthe inclined wall at the end of the annular groove 40 in the valve II.Therefore, when the linger is removed from cap 22, tube I8 moves to theleft under the compressure of spring 23, causing the balls 4| to moveradially outwardly and enter the annular groove 40 and ride along theouter surface of rod 20. Retracting movement of tube I8 also moves valveII to the left to the open or active operating position shown in Fig. 3.This opens communication from the supply to the discharge chamber andgas flows to the main burner where it is ignited by the pilot llame.

The parts remain in the active or operating position until the pilotiiame goes out. When this occurs the thermostatic device cools down, andtube 36 contracts and moves the push rod 38 to the left, thus applyingpressure to the stem extension 3| and to the permanent magnet which itsupports, to an extent sufiicient to bodily move the permanent magnetout of engaging contact with its mating armature member. Thereupon thestem 20 is retracted by the expanding effect of its spring 2|, causingit to return to its original position shown in Fig. 1. Such motionbrings the channel 33 opposite to the balls I4, which enter said channeland therefore are disengaged or freed from the valve member II,releasing the same and permitting it promptly to advance to its safe orclosed position under the inuence of its spring I9. 'I'his brings allparts to their original safe positionsl ready for another cycle of0perations.

It will be observed that in this mechanism the valve housing or body isa single member or casting, without any cap or joint, but cored out toprovide the necessary interior chambers, working parts are attached toand supported by thecentral stem 20 and the thimble 21 in which it ismounted, so that the working parts conveniently may be made andassembled on the bench with all parts exposed to View and convenient forassembly and adjustment. Also, all parts are symmetrically disposedaround the axis of stem 20. YAdvance of the cooking device brings themaintaining or holding devices into close rela- All.

tion, but the actual production of a holding eiect is sensitive to thenecessary variation in temperature produced by ignition of the pilotburner. The production of the holding effect is independent of valvemovement or operation. Retraction of the cooking device opens the valvewithout eifect upon the holding devices which, thereafter, are sensitiveonly to the appropriate variation in the controlling condition, such astemperature.

The mechanism is of simple form, can be made and assembled at low cost,and is highly satisfactory in operation.

What we claim is:

1. Control mechanism of the character described, comprising a hollowbody provided with supply and discharge chambers communicating throughan opening in a cross wall, a valve controlling ilow through saidopening, and a thimble secured in an opening of the body, a stem movablysupported in said thimble, a valve slidable back and forth along saidstem, a holding device advanced by and with said stem to holdingposition when the stem is moved in one direction, a cocking devicecarried by said thimble and slidable on the stem for so moving saidstem, and operating connections between said valve and device foropening the valve when the device is moved in the opposite direction.

2. Control mechanism of the character described, comprising a controldevice movable back and forth between safe and operating positions,

a stem along which said device is movable, hold-1' ing membersrelatively movable longitudinally of the stem into and out of holdingrelation, one of which is secured to -said stem for operative movementthereby, a tubular cooking device slidable on said stem, and meansarranged upon movement of said cooking device in one direction to coupleit to said stem for movement thereof and upon movement in the oppositedirection to coupleit to said control device for movement thereof.

3. Control mechanism of the character described, comprising a controldevice movable back and forth between safe and operating positions, astem along which said device is movable, holding .members relativelymovable into and out of holding relation, one of which is operated bysaid i stern, a tubular cooking device slidable on said stem, meansarranged upon movement of said cooking device in one direction to coupleit to said stem for movement thereof and upon movement in the oppositedirection to couple it to said control device for movement thereof, stopmeans for limiting relative approach of said holding members to aposition in which they are close but out of contact, and thermostaticmeans controlling said stop means for permitting actual contact of saidholding members.

4. Control mechanism of the character described, comprising a controldevice movable back and forth between safe and operating positions, astem along which said device is movable, holding members relativelymovable into and out of holding relation, one of which is operated bysaid stem, a tubular cooking device slidable on said stem, meansarranged upon movement of said` cooking device in one direction tocouple it to said stem for movement thereof and upon movement in theopposite direction to couple it to said control device for movementthereof, stop means for limiting relative approach of said holdingmembers to a position in which they are close but out of contact, andthermostatic means controlling said stop means for permitting actualcontact of said holding members and for separating them when in contactto release the control device.

THOMAS F. VAN DENBERG.

JOHN SELBY.

REFERENCES errno The following references are of record in the file ofthis patent:

UNrrED sTATEs` PATENTS Shaw Aug. 22, 1939

